Downlight with selectable lumens and correlated color temperature

ABSTRACT

A lamp is provided that can have at least one interface on the lamp body for a selectable lumens and selectable correlated color temperature (CCT). In one embodiment, the lamp design includes a housing having a downlight geometry and a light engine including at least one string of light emitting diodes (LEDs), in which the light engine is position to emit light through a light emission end of the housing having the downlight geometry. The lamp also includes at least one first switch for selecting at least one lumen setting for the light emitted by the light engine; and at least one second switch for selecting at least one correlated color temperature. The first and second switch are mounted to the housing.

TECHNICAL FIELD

The present disclosure generally relates to lamp assemblies employinglight emitting diodes as the light source.

BACKGROUND

One of the most common light fixtures is the recessed can downlight(RCD), which is an open-bottom can that contains a light bulb, mostcommonly an incandescent bulb or a fluorescent bulb. The fixture istypically connected to the power mains at 120 to 277 volts, 50/60 Hz.RCDs are generally installed during the construction of a buildingbefore the ceiling material (such as plaster or gypsum board) isapplied. Therefore, they are not easily removed or substantiallyreconfigured during their lifetime. Recently, lighting devices have beendeveloped that make use of light emitting diodes (LEDs) for a variety oflighting applications. Owing to their long lifetime and high energyefficiency, LED lamps are now also designed for replacing traditionalincandescent and fluorescent lamps, i.e., for retrofit applications. Forsuch applications, the LED retrofit lamp is typically adapted to fitinto the socket of the respective lamp fixture to be retrofitted.

SUMMARY

In one aspect, a lamp is provided that can have at least one interfaceon the lamp body for a selectable lumens and selectable correlated colortemperature (CCT). In one embodiment, the lamp design includes a housinghaving a downlight geometry and a light engine including at least onestring of light emitting diodes (LEDs), in which the light engine ispositioned to emit light through a light emission end of the housinghaving the downlight geometry. The lamp also includes at least one firstswitch for selecting at least one lumen setting for the light emitted bythe light engine; and at least one second switch for selecting at leastone correlated color temperature. The first and second switch aremounted to the housing.

In another embodiment, a lamp is provided that includes a housing havinga downlight geometry and a light engine including at least one string oflight emitting diodes (LEDs), in which the light engine is positioned toemit light through a light emission end of the housing having thedownlight geometry. The lamp also includes at least one first switch forselecting at least one lumen setting for the light emitted by the lightengine; and at least one second switch for selecting at least onecorrelated color temperature. The first and second switch are mounted tothe housing. In addition to the light engine being in electricalcommunication with the first and second switch for selecting settingsfor correlated color temperature and lumen setting, the light engine mayalso be in electrical communication with a receiver for receivingsetting commands for dimming and intensity of the light being emitted bythe lamp.

In another embodiment, a lighting method is provided. The lightingmethod includes housing a light source including at least one string oflight emitting diodes in a body of a lamp having a downlight geometry.The method also includes providing device circuitry that allows foradjustments to lumen settings and correlated color temperature settingsthrough an interface of setting switches fixed to the body of the lamp.The method also includes providing a receiver for receiving from aremote switch adjustments to dimming and intensity settings for lightemitted by the lamp.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description will provide details of embodiments withreference to the following figures wherein:

FIG. 1A is a perspective view of lamp design including a housing havinga downlight geometry and a light engine including at least one string oflight emitting diodes (LEDs), in which the lamp also includes at leastone first switch for selecting at least one lumen setting for the lightemitted by the light engine, and at least one second switch forselecting at least one correlated color temperature (CCT), in accordancewith one embodiment of the present disclosure.

FIG. 1B is a magnified perspective view of the first and second switchesfor selecting the lumen settings and correlated color temperature (CCT)that is depicted in FIG. 1A, in which the first and second switches aremounted to the housing.

FIG. 2 is a perspective view of lamp design including a housing having adownlight geometry and a light engine including at least one string oflight emitting diodes (LEDs), in which the lamp also includes a switchfor selecting at least one lumen setting for the light emitted by thelight engine fixed to the housing, an “ON”/“OFF” wall switch forselecting at least one correlated color temperature (CCT), and a remotedimmer switch for adjusting the dimming/intensity of the light emittedby the lamp, in accordance with one embodiment of the presentdisclosure.

FIG. 3 is a perspective view of lamp design including a housing having adownlight geometry and a light engine including at least one string oflight emitting diodes (LEDs), in which the lamp also includes a switchfor selecting at least one correlated color temperature (CCT) settingfor the light emitted by the light engine fixed to the housing, an“ON”/“OFF” wall switch for selecting at least one lumen setting forlight emitted by the lamp, and a remote dimmer switch for adjusting thedimming/intensity of the light emitted by the lamp, in accordance withone embodiment of the present disclosure.

FIG. 4A is a perspective view of a downlight geometry lamp that has beentilted to depict the light engine including at least one string of lightemitting diodes, in which the lamp design includes at least one firstswitch for selecting at least one lumen setting for the light emitted bythe light engine, and at least one second switch for selecting at leastone correlated color temperature (CCT), in accordance with oneembodiment of the present disclosure.

FIG. 4B is a cross-sectional view of the lamp design depicted in FIG.4A.

FIG. 5A is a top down view of a light engine including at least onestring of light emitting diodes (LEDs) as used in the lamp designsdepicted in FIGS. 1A-4B.

FIG. 5B is a perspective view of the light engine depicted in FIG. 5A.

FIG. 6 is a circuit diagram for the electronics package of oneembodiment of the lamp designs that is depicted in FIGS. 1A-4B.

FIG. 7 is a block diagram illustrating a driver for use with the atleast one embodiment of the downlights described with reference to FIGS.1A-6.

DETAILED DESCRIPTION

Reference in the specification to “one embodiment” or “an embodiment” ofthe present invention, as well as other variations thereof, means that aparticular feature, structure, characteristic, and so forth described inconnection with the embodiment is included in at least one embodiment ofthe present invention. Thus, the appearances of the phrase “in oneembodiment” or “in an embodiment”, as well any other variations,appearing in various places throughout the specification are notnecessarily all referring to the same embodiment.

In some embodiments, the present disclosure provides a downlight withselectable lumens settings and selectable correlated color temperature(CCT) settings, in which the settings can be selected by switches thatare fixed to the body of the downlight. The methods and structuresdescribed herein can provide different light output (lumen) levels anddifferent light color levels (CCTs) in a single downlight. In someembodiments, via selectable switch, a lighting designer can adapt thedownlight to an application space by selecting appropriate light andcolor levels. The switch gear for selecting the light levels and/or thelight color levels can be either provided on the downlight as selectableswitches, or can be provided by a combination of selectable switches onthe light housing and a remote wall ON/OFF switch. In some embodiments,the downlights that are described herein provide selectable/switchablelight level and light color settings in a single downlight for both newconstruction and retrofit applications. In some examples, the downlightstructures having selectable/switchable light level and light colorsettings that can include switchgear fixed to the housing (also referredto as body) of the downlight structures offers good flexibility to alighting designer or specifier for selecting either different lightoutput levels (three light output levels of 700/900/1500 lumens) or thelight colors (CCTs of 3000K/3500K/4000K). In some embodiments, theselector switches for selecting the different types of light outputlevel, e.g., lumen levels, and/or different types of light color, e.g.,correlated color temperature (CCT) settings, are device mounted on asingle unit. The light designs of the present disclosure are suitablefor 120-277V applications and can be 0-10V dimmable.

Prior to the lighting structures and methods of the present disclosure,if a lighting designer/user wanted different light levels and/or wantedto use different light color (CCT) the user had to remove the alreadyinstalled unit and replace it with another unit with desired unit withappropriate light output and/or the light color (CCT). This increasedthe cost of the installation, i.e., both the system and labor costs.

By employing the methods and structures of the present disclosure,including the downlight having device mounted selector switches forselecting the different types of light output level, e.g., lumen levels,and/or different types of light color, e.g., correlated colortemperature (CCT) settings, are on a single unit, a lighting designerscan now consider having different light levels in combination withdifferent light colors (CCT) which offers more flexibility withoutincurring the costs of prior downlights not having selectable lightsettings. The lamp structures of the present disclosure are nowdescribed with greater detail with reference to FIGS. 1A-6.

FIGS. 1A, 1B, 4A and 4B depict one embodiment of a downlight 100including a light engine having a plurality of solid state lightemitters, e.g., light emitting diodes (LEDs) 50. A “downlight”, orrecessed light, (also pot light in Canadian English, sometimes can light(for canister light) in American English) is a light fixture that isinstalled into a hollow opening in a ceiling. When installed it appearsto have light shining from a hole in the ceiling, concentrating thelight in a downward direction as a broad floodlight or narrow spotlight.“Pot light” or “canister light” implies the hole is circular and thelighting fixture is cylindrical, like a pot or canister. Broadly, thereare three parts to a downlight fixture: 1) housing, 2) trim and 3) lightengine. It is noted that this is not an exclusive list of the elementsof a downlight fixture. The trim 5 is the visible portion of thedownlight. The trim 5 is the insert that is seen when looking up intothe fixture, and also includes the thin lining around the edge of thelight. The housing 10 is the fixture itself that is installed inside theceiling and contains the lamp holder. It is noted that embodiments arecontemplated in which the trim 5 and the housing 10 are integratedtogether in one piece, and there are embodiments in which the trim 5 andthe housing 10 are separate components. There are many different typesof light engines 60 that can be inserted into recessed lightingfixtures, i.e., downlights 100. In accordance with the embodiments ofthe present disclosure, the light engines 60 applicable to the methodsand structures described herein include solid state emitters, such aslight emitting diodes (LEDs) 50.

The housing 10 may be composed of a metal, such as aluminum (Al), whichprovides for heat dissipation of any heat produced by the light engine15. In some embodiments, to provide for increased heat dissipation, aplurality of ridges or fin structures may be integrated into thealuminum housing 10. In some embodiments, the housing 10 may also becomposed of a plastic, such a polycarbonate. The construction of thehousing 10 may fall into one of four categories for downlights that arerecognized in North America. For example, the housing may be constructedfor IC or “insulation contact” rated new construction housings areattached to the ceiling supports before the ceiling surface isinstalled. If the area above the ceiling is accessible these fixturesmay also be installed from within the attic space. IC housings aretypically required wherever insulation will be in direct contact withthe housing. Non-IC rated new construction housings are used in the samesituations as the IC rated new construction housings, only they requirethat there be no contact with insulation and at least 3 in (7.6 cm)spacing from insulation. These housings are typically rated up to 150watts. IC rated remodel housings are used in existing ceilings whereinsulation will be present and in contact with the fixture. Non-IC ratedremodel housings are used for existing ceilings where, no insulation ispresent. Non-IC rated remodel housings require that there be no contactwith insulation and at least 3 in (7.6 cm) spacing from insulation.Sloped-ceiling housings are available for both insulated andnon-insulated ceilings that are vaulted. It is noted that the housing 10of the downlight of the present disclosure may be designed to meet therequirements of any of the aforementioned standards. The housing 10 istypically designed to ensure that no flammable materials come intocontact with the hot lighting fixture.

The housing 10 may be dimensioned to be available in various sizes basedon the diameter of the circular opening where the downlight 100 isinstalled. In some examples, the circular opening of the housing 10 maybe sized in 4, 5 and 6 inch diameter. It is noted that these dimensionsare provided for illustrative purposes only and are not intended tolimit the present disclosure. For example, the housing 10 may also havea circular opening in diameters equal to 2 inches or 3 inches. Theopening of the housing may also be multi-sided, such as square orrectangular.

In some embodiments, the housing 10 can also be “Air Tight”, which meansit will not allow air to escape into the ceiling or attic, thus reducingboth heating and cooling costs.

The trim 5 of the downlight 100 is selected to increase the aestheticappearance of the lamp. In some embodiments, the trim 5 may be a bafflethat is black or white in color. In some embodiments, the trim 5 is madeto absorb extra light and create a crisp architectural appearance. Thereare cone trims which produce a low-brightness aperture. In someembodiment, the trim 5 may be a multiplier that is designed to controlthe omnidirectional light from the light engine. Lens trim is designedto provide a diffused light and protect the lamp. Lensed trims arenormally found in wet locations. The luminous trims combine the diffusedquality of lensed trim but with an open down light component. Adjustabletrim allows for the adjustment of the light whether it is eyeball style,which protrudes from the trim or gimbal ring style, which adjusts insidethe recess.

The light engine (also referred to as light source) is positioned withinthe housing 10 and orientated to emit light in a direction throughopening of the housing 10 at which the trim 5 is positioned. The lightengine produces light from solid state emitters.

The term “solid state” refers to light emitted by solid-stateelectroluminescence, as opposed to incandescent bulbs (which use thermalradiation) or fluorescent tubes, which use a low pressure Hg discharge.Compared to incandescent lighting, solid state lighting creates visiblelight with reduced heat generation and less energy dissipation. Someexamples of solid state light emitters that are suitable for the methodsand structures described herein include inorganic semiconductorlight-emitting diodes (LEDs), organic light-emitting diodes (OLED),polymer light-emitting diodes (PLED) or combinations thereof. Althoughthe following description describes an embodiment in which the solidstate light emitters are provided by light emitting diodes, any of theaforementioned solid state light emitters may be substituted for theLEDs. FIGS. 5A and 5B illustrate one example of the light emittingdiodes (LEDs) 50 of a light engine 60 that can be utilized within thedownlights 100 that are depicted in FIGS. 1A-4B.

Referring to FIGS. 5A and 5B, in some embodiments, the light source(also referred to as light engine) for the downlight 100 is provided byplurality of LEDs 50 that can be mounted to the circuit board 60 bysolder, a snap-fit connection, or other engagement mechanisms. In someexamples, the LEDs 50 are provided by a plurality of surface mountdevice (SMD) light emitting diodes (LED).

The circuit board 70 for the light engine 60 may be composed of a metalcore printed circuit board (MCPB). MCPCB uses a thermally conductivedielectric layer to bond circuit layer with base metal (Aluminum orCopper). In some embodiments, the MCPCB use either Al or Cu or a mixtureof special alloys as the base material to conduct heat away efficientlyfrom the LEDs thereby keeping them cool to maintain high efficacy. Insome other embodiments, the PCB type may be FR4 or CEMI.

It is noted that the number of LEDs 50 on the printed circuit board 70may vary. For example, the number of LEDs 50 may range from 5 LEDs to 70LEDs. In another example, the number of LEDs 50 may range from 35 LEDsto 45 LEDs. It is noted that the above examples are provided forillustrative purposes only and are not intended to limit the presentdisclosure, as any number of LEDs 50 may be present the printed circuitboard 70. In some other examples, the number of LEDs 50 may be equal to5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65 and 70, as well as anyrange of LEDs 50 with one of the aforementioned examples as a lowerlimit to the range, and one of the aforementioned examples as an upperlimit to the range.

The LEDs 50 may be arranged as strings on the printed circuit board 70.When referring to a “string” of LEDs it is meant that each of the LEDsin the string are illuminated at the same time in response to anenergizing act, such as the application of electricity from the drivingelectronics, e.g., driver, in the downlight 100. The LEDs 50 in a stringof LEDs are electrically connected for this purpose. For example, whenthe a string of LEDs 50 is energized for illumination, all of the LEDsin the string are illuminated. Further, in some embodiments,illuminating the first string of LEDs 50 does not illuminate the LEDs inthe second string of LEDs 50, and vice versa, as they are independentlyenergized by the driving electronics, and not electrically connected. Itis also noted that the same LED may be shared by more than one string.

In one example, a first string of LEDs 50 may be illuminated to providean intensity of light emitted by the light engine 60 for the downlight100 that is on the order of 500 lumens (LM), a second string of LEDs 50may be illuminated to provide an intensity of light emitted by the lightengine 60 for the downlight 100 that is on the order of 900 lumens (LM);and a third string of LEDs 50 may be illuminated to provide an intensityof light emitted by the light engine 60 for the downlight 100 that is onthe order of 1500 lumens (LM).

In another example, a fourth string of LEDs 50 may be illuminated toprovide an correlated color temperature (CCT) of light emitted by thelight engine 60 for the downlight 100 that is on the order of 2700K, afifth string of LEDs 50 may be illuminated to provide an correlatedcolor temperature (CCT) of light emitted by the light engine 60 for thedownlight 100 that is on the order of 3500K; and a sixth string of LEDs50 may be illuminated to provide an intensity of light emitted by thelight engine 60 for the downlight 100 that is on the order of 4000K.

It is noted that the above examples of LED strings are consistent withthe selectable settings for light emitted by the downlight 100 that aredepicted in FIGS. 1A and 1B. The present disclosure is not limited toonly this example, as other lighting characteristics can be assigned tostrings of LEDs that can be selected by a user through the interfaceswith the downlight 100 that are described herein.

In some embodiments, the LEDs 50 of the lamp 100 are selected to becapable of being adjusted for the color of the light they emit. The term“color” denotes a phenomenon of light or visual perception that canenable one to differentiate objects. Color may describe an aspect of theappearance of objects and light sources in terms of hue, brightness, andsaturation. Some examples of colors that may be suitable for use withthe method of controlling lighting in accordance with the methods,structures and computer program products described herein can includered (R), orange (O), yellow (Y), green (G), blue (B), indigo (I), violet(V) and combinations thereof, as well as the numerous shades of theaforementioned families of colors. It is noted that the aforementionedcolors are provided for illustrative purposes only and are not intendedto limit the present disclosure as any distinguishable color may besuitable for the methods, systems and computer program productsdescribed herein.

The LEDs 50 of the lamp 100 may also be selected to allow for adjustingthe “color temperature” of the light they emit. The color temperature ofa light source is the temperature of an ideal black-body radiator thatradiates light of a color comparable to that of the light source. Colortemperature is a characteristic of visible light that has applicationsin lighting, photography, videography, publishing, manufacturing,astrophysics, horticulture, and other fields. Color temperature ismeaningful for light sources that do in fact correspond somewhat closelyto the radiation of some black body, i.e., those on a line fromreddish/orange via yellow and more or less white to blueish white. Colortemperature is conventionally expressed in kelvins, using the symbol K,a unit of measure for absolute temperature. Color temperatures over 5000K are called “cool colors” (bluish white), while lower colortemperatures (2700-3000K) are called “warm colors” (yellowish whitethrough red). “Warm” in this context is an analogy to radiated heat fluxof traditional incandescent lighting rather than temperature. Thespectral peak of warm-colored light is closer to infrared, and mostnatural warm-colored light sources emit significant infrared radiation.The LEDs 50 of the lamps provided by the present disclosure in someembodiments can be adjusted from 2000K to 7000K.

The LEDs 50 of the lamp 100 may also be selected to be capable ofadjusting the light intensity/dimming of the light they emit. In someexamples, dimming or light intensity may be measured using lumen (LM).In some embodiments, the dimming or light intensity adjustment of theLEDs 50 can provide for adjusting lighting between 100 LM to 2000 LM. Inanother embodiment, dimming or light intensity adjustment of the LEDs 50can provide for adjusting lighting between 500 LM to 1750 LM. In yetanother embodiment, the dimming or light intensity adjustment of theLEDs 50 can provide for adjusting lighting between 700 LM to 1500 LM.

In some embodiments, the LED light engines 60 for the downlight mayprovide the that downlight be an SMD (Surface Mount Diode) downlightand/or a COB (Chip on Board) downlights. In some embodiments, the LEDs50 may be selected to be SMD type emitters, in which the SMDs are moreefficient than COBs because the light source produces higher lumens perwatt, which means that they produce more light with a lower wattage. Insome embodiments, the SMD type LEDs 50 can produce a wider beam of lightwhich is spread over a greater area when compared to light engines ofCOB type LEDs. This means that less material is needed for the heatsink, which in turn means that they are more economical. SMD downlightscan be covered with a frosted reflector which hides the LED chip array,and spreads the light evenly. SMD downlights can produce a wide spreadof light. In some example, the wide beam angle of the light emitted fromSMD downlights means they can be suitable for larger rooms like livingrooms, bedrooms, kitchens and bathrooms.

A Chip On Board (COB) LED Downlight consists of a single LED chip,mounted on the downlight, compared to an array of LED's like an SMD. COBLEDs are basically multiple LED chips (typically nine or more) bondeddirectly to a substrate by the manufacturer to form a single module. Theceramic/aluminum substrate of COB LEDs also acts as a higher efficiencyheat transfer medium when coupled to an external heatsink, furtherlowering the overall operating temperature of the assembly. Since theindividual LEDs used in a COB are chips, the chips can be mounted suchthat they take up less space and the highest potential of the LED chipscan be obtained. When the COB LED package is energized, it appears morelike a lighting panel than multiple individual lights as would be thecase when using several SMD LEDs mounted closely together. In someembodiments, because the single cluster of LED's 50 are mounted in onepoint, they can require greater cooling, so a heat sink, usually made ofaluminum, may be mounted to dissipate the heat.

A light engine of COB type LEDs 50 can provide a more focused light andwith the use of reflectors, the light beam can be more controlled whencompared to a light engine that is composed of SMD LEDs. Chromereflectors surrounding the diode can be replaced and set at differentangles to make the light beam narrower or wider. Due to the narrow beamand with the use of reflectors that are usually clear, COB lightsgenerate crisper and cleaner as there is no frosting on the lenses,which cuts down the clarity of the LED light. Due to the clear lenses,more light can penetrate further which means they perform well in roomswith high ceilings.

It is noted that the above description of the light emitting diodes(LEDs) 50 is provided for illustrative purposes only, and is notintended to limit the present disclosure. For example, In someembodiments, other light sources may either be substituted for the LEDs50, or used in combination with the LEDs 50, such as organiclight-emitting diodes (OLEDs), a polymer light-emitting diode (PLED),and/or a combination of any one or more thereof.

Referring to FIGS. 1A and 1B, in some embodiments, the downlight 100includes at least one interface on the lamp housing 100 for selecting alumen setting and for selecting a correlated color temperature (CCT)setting for the light being emitted by the light engine 60 of thedownlight 100. In some embodiments, the switch 15 a, 15 b for selectingeach of the settings may be a toggle switch, a pushbutton switch, and/ora selector switch. Toggle switches are actuated by a lever angled in oneof two or more positions. Pushbutton switches are two-position devicesactuated with a button that is pressed and released. Selector switchesare actuated with a rotary knob or lever of some sort to select one oftwo or more positions. Like the toggle switch, selector switches caneither rest in any of their positions or contain spring-returnmechanisms for momentary operation. It is noted that the above examplesare provided for illustrative purposes only, and are not intended tolimit the types of switches that are to be used in accordance with thepresent disclosure. Any switch used to interrupt the flow of electronsin a circuit can be suitable for use as a switch 15 a, 15 b forselecting settings for the lumen output of the light emitted by thedownlight and/or selecting the correlated color temperature (CCT) of thelight emitted by the downlight 100. In one example, a simplest type ofswitch is one where two electrical conductors are brought in contactwith each other by the motion of an actuating mechanism.

Referring to FIGS. 1A and 1B, in one embodiment, the downlight includesa first switch 15 a for selecting at least one lumen setting for thelight emitted by the light engine 60; and a second switch 15 b forselecting at least one correlated color temperature (CCT). In theembodiment that is depicted in FIGS. 1A and 1B, the first switch 15 amay be positioned to select a lumen setting from three possiblesettings, e.g., a first lumen setting of 700 LM, a second lumen settingof 900 LM, and a third lumen setting 1500 LM. In the embodiment that isdepicted in FIGS. 1A and 1B, the second switch 15 b may be positioned toselect a correlated color temperature (CCT) setting from three possiblesettings, e.g., a first correlated color temperature (CCT) setting of2700K, a second correlated color temperature (CCT) setting of 3500K, anda third correlated color temperature (CCT) setting 4000K. In theexample, that is depicted in FIGS. 1A and 1B, the single downlightoffers 9 unique combinations of light levels and color temperaturesettings.

It is noted that the number of selectable settings provided by the firstand second switches 15 a, 15 b depicted in FIGS. 1A and 1B is providedfor illustrative purposes only and is not intended to limit the presentdisclosure. For example, the number of selectable settings that may beselected using the first and second switches 15 a, 15 b may be equal to2, 3, 4, 5, 6, 7, 8, 9 and 10, as well as any range for the number ofselectable settings including a lower limit provided by one of theaforementioned examples, and an upper limit provided by one of theaforementioned examples. Further, the values for the selectablesettings, e.g., lumen settings and correlated color temperature (CCT)settings, are not limited to those described above and depicted in FIGS.1A and 1B.

For example, the first switch 15 a may select at least one lumensetting, e.g., a set of three lumen settings, selected from 500 LM, 600LM, 700 LM, 800 LM, 900 LM, 1000 LM, 1100 LM, 1200 LM, 1300 LM, 1400 LM,1500 LM, 1600 LM, 1700LM, 1800 LM, 1900 LM and 2000 LM, as well as anyrange for the lumens associated with the light emitted by the downlightincluding a lower limit provided by one of the aforementioned examples,and an upper limit provided by one of the aforementioned examples.

For example, the second switch 15 b may select at least one correlatedcolor temperature (CCT) setting selected from 2500K, 2600K, 2700K,2800K, 2900K, 3000K, 3100K, 3200K, 3300K, 3400K, 3500K, 3600K, 3700K,3800K, 3900K, 4000K, 4100k, 4200K, 4300K, 4400K and 4500K, as well asany range for the correlated color temperature (CCT) associated with thelight emitted by the downlight including a lower limit provided by oneof the aforementioned examples, and an upper limit provided by one ofthe aforementioned examples.

The first and second switch 15 a 15 b are mounted to the housing 10. Forexample, the first and second switch 15 a, 15 b may be mounted to thebackside surface of the housing 10, which is opposite the face of thehousing 10 that the trim 5, in which the trim 5 is present about anopening through which the light emitted from the light engine 60 isdirected. The backside surface of the housing 10 is positioned withinthe ceiling when the downlight 100 is installed. It is not necessary forevery embodiment that the first and second switches 15 a, 15 b bemounted to the back surface of the housing 10. In some embodiments, atleast one of the first and second switches 15 a, 15 b may be mounted onthe sidewall of the housing 10, which is the portion of the housingbetween the back surface of the housing 10, and the portion of thehousing that the trim 5 is mounted to. In other embodiments, at leastone of the first and second switches 15 a, a5 b may be mounted to thetrim 5.

In addition to the light engine being in electrical communication withthe first and second switch for selecting settings for correlated colortemperature and lumen setting, the light engine may also be inelectrical communication with a receiver for receiving setting commandsfor dimming and intensity of the light being emitted by the lamp. Insome embodiments, the dimming function may be controlled through a 0-10Vdimming wall switch. The 0-10V dimming wall switch is remotely mountedfrom the housing 10 of the downlight 100. The 0-10V dimming wall switchcommunicates with a 0-10V dimming circuit 71 in the electronics package200 of the downlight 100.

Referring to FIG. 6, the 0-10V dimming circuit 71 is in electriccommunication with a 0-10V dimming input 72 that receives the signalfrom the 0-10V dimming wall switch. The 0-10V dimming circuit 71 is inelectrical communication with the LEDs 50, i.e., strings of LEDs 50 ofthe light engine 60. The 0-10V dimming circuit 71 may be referred to asa 0-10 dimmable LED driver.

In lighting control applications, “0-10” describes the use of an analogcontroller to adjust the voltage in a 2-wire (+10VDC and Common) busconnecting the controller to one or more LED drivers equipped with a0-10VDC dimming input. A 0-10V dimmable LED driver includes a powersupply circuit that produces approximately 10VDC for the signal wiresand sources an amount of current in order to maintain that voltage. Thecontrolled lighting should scale its output so that at 10 V, thecontrolled light should be at 100% of its potential output, and at 0 Vit should at the lowest possible dimming level.

A 0-10V LED dimmable driver designs with a control chip. The 0-10Vvoltage changes, the power supply output current will change. Forexample, when the 0-10V dimming signal modulates to 0V, the outputcurrent will be 0, the brightness of the light will be off; when the0-10V dimming modulates to maximum 10V, the output current will reach100% power output, the brightness will be 100%.

The electronics package 200 including the receiver, i.e., input 72, forthe 0-10V wall switch may be mounted within the house 10, as depicted inFIG. 4B. In some embodiments, although not depicted in the suppliedfigures, at least some components of the electronics package 200 may bepositioned outside the housing 10 in a remote electronics package.

Referring to FIG. 6, in some embodiments the electronics package 200 forthe downlight 100 may further include: EMI filter and surge protection73, bridge rectifier and filter 74, flyback converter 75, currentswitching scheme 76, optical/magnetic isolation of the feedback 77, LEDstrings, 60 and LED string switching scheme 78.

The EMI filter and surge protection 73 portion of the electronicspackage 200 includes an EMI filter to filter the high frequency noisegenerated by the flyback converter from entering the mains inputterminals of line and neutral. The surge protector protects the lampfrom the surge caused by events such as lightning and disturbances onthe mains grid. The Surge protector absorbs the energy and limits thepeak voltage to a safe level.

The bridge rectifier and filter 74 portion of the electronics package200 includes a bridge rectifier that rectifies the AC input voltage intoa pulsating DC voltage. The filter filters the high frequency noise.

The flyback converter 75 portion of the electronics package 200 containsthe flyback transformer, switch, flyback controller, starting resistor,secondary rectifier and ripple current filter. This section of theelectronics package 200 generates the required voltage and current asper the need of the LED strings 50. This section also provides thenecessary isolation between the input and output.

The current switching scheme 76 portion of the electronics package 200includes the switch 15 a that the user can control the lumen output ofthe downlight 200. In some embodiments, this is done by changing theoutput current of the power supply going into the LEDs. The currentswitching circuit consists of a network and combination of differentvalues of current sense resistors. Depending on the switch positionspecific part of the circuit is activated and the sense resistors inthat branch circuit determines the current flowing into the power supplyoutput and hence the LEDs 50. The switching scheme 76 changes thefeedback signal into the controller IC 75 based on the position of theswitch 15 a. The IC will control the current based on that feedbacksignal.

The optical/magnetic isolation circuit 77 portion of the electronicspackage 200 provides electrical isolation of the control signal from the0 to 10V dimming circuit 71 going into the flyback controller IC. Insome instances, this isolation can provide for the safety of the userwhen installing or operating the 0 to 10V dimmer.

The 0 to 10V dimming circuit 71 of the electronics package 200 acceptsthe input from the 0 to 10V dimmer and generates corresponding signalfor the flyback controller IC. This enables the change of output currentfrom power supply going into LEDs to be controlled by the external 0 to10V dimmer.

The LED string 50 portion of the electronics package 200 includes thecircuitry to the number of LEDs, and the number of LED strings. The LEDtype, e.g., color temperature, can be chosen based on the requirementfor the light output characteristics. These LED strings are driven bythe voltage and current generated by the flyback converter and theygenerate the required optical characteristics.

LED string switching scheme 78 portion of the electronics package 200 isa circuit determines which string, i.e., string of LEDs 50, is operatingbased on the users' selection of the switch position 15 a, 15 b.Accordingly, it may operate just one string of LEDs 50, or more than onestring of LEDs 50 based on the correlated color temperature (CCT)setting of the switch 15 b. In the example provided in FIGS. 1A and 1B,in which the switch 15 b for selecting the correlated color temperature(CCT) of the downlight 100 has three selectable positions, i.e., threepositions for color correlated temperature (CCT) values that are equalto 2700K, 3500K and 4000K. In some examples, each setting that can beselected by the switch 15 b may energize a different LED string of LEDs50 for each of the three different color correlated temperature (CCT)values. In another embodiment, the lamp interface, i.e., switch 15 b,may offer three light color options (CCTs of 2700K/3500K/4000K), but thedesign of the light engine 60 may only include two strings of LEDs,e.g., only a first string of LEDs 50 having a correlated colortemperature (CCT) of 2700K and second string of LEDs 50 having acorrelated color temperature (CCT) of 4000K. In this example, when auser selects the 3500K setting from the switch 15 b, this light color isachieved by mixing light from both the 2700K and 4000K LEDs, which isachieved by the LED string switching scheme.

In one example, to achieve light levels 700 LM, 900 LM and 1500 LM, aswell selectable correlated color temperature (CCT) levels of 3000k,3500k, and 4000K, the following LED type and circuit can be employed: 1)the LED type may be lumileds 6V (forward voltage of LEDs) & 1W LEDs, and20 LEDs of CCT 3000K in 2 parallel strings of 10 LEDs in series, and 20LEDs of CCT 4000K in 2 parallel strings of 10 LEDs in series to providea total quantity of 40 LEDs.

The downlight design depicted in FIGS. 1A, 1B, 4A and 4B is only oneembodiment of the present disclosure, and it is not intended that thepresent disclosure be limited to only this example. For example, inaddition to switches being fixed to the housing 10 of the downlight forselecting lighting characteristics, embodiments of the presentdisclosure combine this capability with lighting controls throughtoggling of a remote “ON/OFF” switch,

FIG. 2 depicts one embodiment of a lamp design including a housing 10having a downlight geometry and a light engine 60 including at least onestring of light emitting diodes (LEDs), in which the lamp also includesa switch 15 a for selecting at least one lumen setting for the lightemitted by the light engine 60 fixed to the housing, an “ON”/“OFF” wallswitch 90 for selecting at least one correlated color temperature (CCT),and a remote dimmer switch 95, i.e., 0-10V dimmer wall switch, foradjusting the dimming/intensity of the light emitted by the lamp. Thehousing 10, the light engine 60 (including the LEDs 50), the switch 15 aand the remote dimmer switch 95 have all been described above for theembodiments described with reference to FIGS. 1A, 1B and 4A-6. Thedescription of those elements with reference to FIGS. 1A, 1B and 4A-6can provide at least one embodiment of these elements for the samestructures in FIG. 2. For example, the light levels emitted by thedownlight 100, i.e., lumen values, can be adjusted via the switch 15 aon the back of the unit. In one example, the selectable lumen levels oflight may be equal to 700 LM, 900 LM and 1500 LM.

In the embodiment that is depicted in FIG. 2, the correlated colortemperature (CCT) of the light being emitted by the downlight may beselecting through a wall ON/OFF switch. In one example, when the lightengine 60 is configured to provide for three selectable correlated colortemperatures (CCTs), which can include 2700K, 3500K, and 4000K, thelight color (CCT) is switched between the three options by flipping thewall ON/OFF switch until the desired CCT is selected.

FIG. 3 depicts one embodiment of a lamp design including a housing 10having a downlight geometry and a light engine 60 including at least onestring of light emitting diodes (LEDs), in which the lamp also includesa switch 15 b for selecting at least one correlated color temperature(CCT) setting for the light emitted by the light engine fixed to thehousing, an “ON”/“OFF” wall switch for selecting at least one lumensetting for light emitted by the lamp, and a remote dimmer switch foradjusting the dimming/intensity of the light emitted by the lamp.

The housing 10, the light engine 60 (including the LEDs 50), the switch15 b and the remote dimmer switch 95 have all been described above forthe embodiments described with reference to FIGS. 1A, 1B and 4A-6. Thedescription of those elements with reference to FIGS. 1A, 1B and 4A-6can provide at least one embodiment of these elements for the samestructures in FIG. 2. For example, the correlated color temperature(CCT) values for the light emitted by the downlight 100 can be adjustedvia the switch 15 b on the back of the unit. In one example, theselectable correlated color temperature (CCT) values of light may beequal to 2700K, 3500K and 4000K.

To provide for switching between light modes, i.e., different settingsfor light lumens and correlated color temperature of light, beingemitted by the downlight using an ON/OFF light switch 90, as describedwith reference to FIGS. 2 and 3 the downlight 100 may have to employ adriver 124 having a design similar to that depicted in FIG. 7.

The switch 90 may be in wired or wireless communication with thedownlight 100. In some embodiments, when the downlight 100 is turned oninitially by toggling the switch 90 to its ON position, the downlight100 will enter its first emission mode 127 e.g., a first correlatedcolor temperature of 2700K or a first lumen level of 700 LM. If thedownlight 100 is then turned off (by toggling the switch 90 into its offposition) and on again (by toggling the switch 90 to its on position)within a specified time window, the downlight 100 can enter the secondemission mode 128, e.g., a second correlated color temperature of 3500Kor a second lumen level of 900 LM. If the downlight 100 is thereafterturned off again (by toggling the switch 90 into its off position) andon again (by toggling the switch 90 to its on position) within aspecified time window, the downlight 100 can enter the third emissionmode 129, e.g., a third correlated color temperature of 4000K or a thirdlumen level of 1500 LM. If the downlight 100 is thereafter turned offagain (by toggling the switch 90 into its off position) and on again (bytoggling the switch 90 to its on position) within a specified timewindow, the downlight 100 will return to the first emission mode 127,e.g., a first correlated color temperature of 2700K or a first lumenlevel of 700 LM.

The duration of each of time window for toggling the switch 90 to changelighting modes may be customized, as desired, and in at least some casesmay be about 3 seconds or less. For example, in some embodiments, theduration of the time windows may be about 2.5 seconds or less. Inanother example, the duration of the time windows may be about 2 secondsor less. In yet another example, the duration of each of the timewindows may be about 1.5 seconds or less. In some instances, either (orboth) the first and second time windows may be user-programmable.

Referring to FIG. 7, in some embodiments, the driver 124 may be asingle-channel or multi-channel electronic driver configured to drivethe solid state light emitters, e.g., LEDs of the first and secondstrings of LEDs 50 a, 50 b, utilizing pulse-width modulation (PWM)dimming or any other suitable standard, custom, or proprietary drivingtechniques. As further shown in FIG. 7, the driver 124 may include acontroller 130. In accordance with some embodiments, the driver 124 maybe configured to provide a downlight 100 with a three-mode operation;that is, the driver 124 may provide downlight 100 with: (1) a firstemission mode 127 e.g., a first correlated color temperature of 2700K ora first lumen level of 700 LM; (2) a second emission mode 128, e.g., asecond correlated color temperature of 3500K or a second lumen level of900 LM; and (3) a third emission mode 129, e.g., a third correlatedcolor temperature of 4000K or a third lumen level of 1500 LM.

In some embodiments, the downlight 100 having the three aforementionedlight modes, i.e., first emission mode 127, a second emission mode 128,and third emission mode 129 (having settings set depending upon beingpracticed in the embodiments illustrated in FIG. 2 or 3) depending uponthe application to the driver 124 to the embodiments depicted in FIGS. 2and 3 may be driven by the driver 124 including a controller 130configured to support mode changing for the lamp 100 based, in part orin whole, on hysteresis. For example, mode changing of the downlight 100may be based, in part or in whole, on the hysteresis phenomena of aswitch 90, e.g., light switch, in operation toggling between ON and OFFelectrical states. In accordance with some embodiments, the output ofLEDs for the first and second string of LEDs 50 a, 50 b, and thus thedownlight 100 may be electronically controlled by controller 130. Tosuch ends, the controller 130 may be operatively coupled with the LEDsof the first and second string of LEDs 50 a, 50 b (or light engine 69more generally), for instance, by a communication bus or other suitableinterconnect. In some embodiments, the controller 130 may be configuredto communicate with the LEDs, i.e., solid state light emitters, via anyone, or combination, of suitable standard, custom, or proprietary wiredor wireless digital communications protocol.

In accordance with some embodiments, the first emission mode 127, thesecond emission mode 128, and the third emission mode 129 (havingsettings set depending upon being practiced in the embodimentsillustrated in FIG. 2 or 3) of the controller 130 may be implemented inany suitable standard, custom, or proprietary programming language, suchas, for example, C, C++, objective C, JavaScript, or any other suitableinstruction set, as will be apparent in light of this disclosure. Themodule(s) of controller 130 can be encoded, for example, on amachine-readable medium that, when executed by a processor, carries outthe functionality of downlight 100, in part or in whole. Thecomputer-readable medium may be, for example, a hard drive, a compactdisk, a memory stick, a server, or any suitable non-transitory computeror computing device memory that includes executable instructions, or aplurality or combination of such memories. Some embodiments can beimplemented, for instance, with gate-level logic, anapplication-specific integrated circuit (ASIC) or chip set, or othersuch purpose-built logic. Some embodiments can be implemented with amicrocontroller having input/output capability (e.g., inputs forreceiving user inputs; outputs for directing other components) andembedded routines for carrying out device functionality. In a moregeneral sense, the functional modules of controller 130 can beimplemented in any one, or combination, of hardware, software, andfirmware, as desired for a given target application or end-use.

Moreover, in some embodiments, a given module of controller 130 (orcontroller 130 more generally) may be programmable to achieve any of thevarious functions and emissions capabilities desired of downlight 100for a given target application or end-use. The present disclosure is notintended to be limited only to these example lighting control modulesand output signals; as additional and/or different lighting controlmodules and output signals may be provisioned, as desired for a giventarget application or end-use.

Further, it is not intended to be limited only to drivers 124 includingthese specific example controllers 130. In a more general sense, and inaccordance with some other embodiments, controller 130 can be any powersupply controller IC or microcontroller having the ability to sense theoperation of the input power (e.g., based on the on/off state of switch90, discussed below) while maintaining a hysteresis from on-to-off andoff-to- on control, with LED string control being provided bycontrolling the on/off state of the LEDs in the first and second stringof LEDs 50 a, 50 b. In some still other cases, controller 130 may be amicrocontroller programmed to receive a control input from a wired orwireless source other than, or in addition to, a switch (e.g., such asswitch 90) and accordingly generate a target mode of lighting, e.g. thefirst emission mode 127, the second emission mode 128, and the thirdemission mode 129 (having settings set depending upon being practiced inthe embodiments illustrated in FIG. 2 or 3), by controlling the dutycycle of the first and second string of LEDs 50 a, 50 b.

Returning to FIG. 7, the downlight 100 optionally may include acommunication module 126, which may be configured as a transmitter, areceiver, or both (i.e., a transceiver). In some cases, communicationmodule 126 may be separate and distinct from controller 130 (e.g., asgenerally shown in FIG. 7), though in some other cases, communicationmodule 126 may be a component of or otherwise integrated with controller130. In accordance with some embodiments, controller 130 may beconfigured to output control signal(s) to the first and second stringsof LEDs 50 a, 50 b based, at least in part, on input received from aremote source, such as a control interface 140. Control interface 140may be physical, virtual, or a combination thereof and may be configuredto communicate with the controller 130 (via intervening communicationmodule 126), which in turn interprets input received from controlinterface 140 distributes desired control signal(s) to the first andsecond strings of LEDs 50 a, 50 b of the light engine 60.

In some embodiments, the control interface 140 may be employed, inaccordance with some embodiments, in changing the emissions modes ofdownlight 100. In some embodiments, the control interface 140 interactswith the switch 90, e.g., over the communications module 126, as theswitch toggles from the ON and Off electrical states, and provides thesignal to the driver 124. The driver 124 receiving the signal from thecontrol interface employing the controller 130 sends a signal toilluminate either the string of LEDs 50 a, 50 b to provide the firstemission mode 127, the second emission mode 128, or the third emissionmode 129 (having settings set depending upon being practiced in theembodiments illustrated in FIG. 2 or 3).

To such ends, the communication module 126 and control interface 140 maybe configured for wired or wireless communication (or both) utilizingany one, or combination, of suitable means, such as Universal Serial Bus(USB), Ethernet, FireWire, Wi-Fi, Bluetooth, or ZigBee, among others.Optionally, the control interface 140 may be or otherwise employ atouch-sensitive display or surface, such as a touchpad or other devicewith a touch-based user interface (UI) or graphical UI (GUI), asprovided by a computing device, mobile or otherwise. Other suitableconfigurations for the communication module 126 and the controlinterface 65 will depend on a given application.

In another aspect, a lighting method is provided. The lighting methodincludes housing a light source, e.g., light engine 60, including atleast one string of light emitting diodes 50 in a body of a lamp havinga downlight geometry. The method also includes providing devicecircuitry, as depicted in FIGS. 6 and 7, that allows for adjustments tolumen settings and correlated color temperature settings through aninterface of setting switches fixed to the body of the lamp. The methodalso includes providing a receiver for receiving from a remote switch90, 95 adjustments to dimming and intensity settings for light emittedby the lamp. Before installing the downlight 100, based on theapplication space, the lighting designer may determine the desired lightoutput and the light color needs. Using the light level switch 15 a, andthe light color level switch 15 b on the back of the unit, as depictedin FIGS. 1A and 1B, the installer selects appropriate levels for thelight output and the light color levels for the downlight 100. The usermay then install the downlight 100. As needed by the application space,the light levels and/or the light color levels can be changed byuninstalling the unit and adjusting the switches to the desiredsettings.

It is to be appreciated that the use of any of the following “/”,“and/or”, and “at least one of”, for example, in the cases of “A/B”, “Aand/or B” and “at least one of A and B”, is intended to encompass theselection of the first listed option (A) only, or the selection of thesecond listed option (B) only, or the selection of both options (A andB). As a further example, in the cases of “A, B, and/or C” and “at leastone of A, B, and C”, such phrasing is intended to encompass theselection of the first listed option (A) only, or the selection of thesecond listed option (B) only, or the selection of the third listedoption (C) only, or the selection of the first and the second listedoptions (A and B) only, or the selection of the first and third listedoptions (A and C) only, or the selection of the second and third listedoptions (B and C) only, or the selection of all three options (A and Band C). This may be extended, as readily apparent by one of ordinaryskill in this and related arts, for as many items listed.

Spatially relative terms, such as “forward”, “back”, “left”, “right”,“clockwise”, “counter clockwise”, “beneath,” “below,” “lower,” “above,”“upper,” and the like, can be used herein for ease of description todescribe one element's or feature's relationship to another element(s)or feature(s) as illustrated in the FIGs. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the FIGs.

Having described preferred embodiments of a downlight having selectablelumens settings and selectable correlated color temperature (CCT), it isnoted that modifications and variations can be made by persons skilledin the art in light of the above teachings. It is therefore to beunderstood that changes may be made in the particular embodimentsdisclosed which are within the scope of the invention as outlined by theappended claims. Having thus described aspects of the invention, withthe details and particularity required by the patent laws, what isclaimed and desired protected by Letters Patent is set forth in theappended claims.

1. A lamp comprising: a housing having a downlight geometry and a lightengine including at least one string of light emitting diodes (LEDs), inwhich the light engine is positioned to emit light through a lightemission end of the housing having the downlight geometry; at least onefirst switch for selecting at least one lumen setting for the lightemitted by the light engine; and at least one second switch forselecting at least one correlated color temperature, wherein the firstand second switch are positioned on the housing, wherein the at leastone first switch and the at least one second switch are mounted on aback surface of the housing.
 2. The lamp recited in claim 1 furthercomprising a dimming circuit for dimming the light emitted by the lampin response to signal from a 0-10V dimming switch.
 3. The lamp recitedin claim 1, wherein the light emitting diodes are surface mount device(SMD) light emitting diodes (LED).
 4. The lamp as recited in claim 1,wherein the light emitting diodes are chip on board (COB) light emittingdiodes.
 5. The lamp as recited claim 1, wherein the first switch hasthree selectable settings of 700 LM, 900 LM and 1500 LM.
 6. The lamp asrecited in claim 1, wherein the second switch has three selectablesettings of 2700K, 3500K and 4000K.
 7. (canceled)
 8. A lamp comprising:a housing having a downlight geometry and a light engine including atleast one string of light emitting diodes (LEDs), in which the lightengine is positioned to emit light through a light emission end of thehousing having the downlight geometry; a switch positioned on thehousing for selecting a first setting for the light emitted by the lightengine, wherein the switch positioned on the housing for selecting thefirst setting is mounted on a back surface of the housing; and areceiver for receiving signal from a remote ON/OFF switch, wherein thesignal from the remote ON/OFF switch selects a second setting for lightemitted by the light engine, wherein the first and second settings areselected from the group consisting of lumen level, color correlatedtemperature or a combination thereof.
 9. The lamp recited in claim 8further comprising a dimming circuit for dimming the light emitted bythe lamp in response to signal from a 0-10V dimming switch.
 10. The lamprecited in claim 8, wherein the light emitting diodes are surface mountdevice (SMD) light emitting diodes (LED).
 11. The lamp as recited inclaim 8, wherein the light emitting diodes are chip on board (COB) lightemitting diodes.
 12. The lamp as recited claim 8, wherein the switchpositioned on the housing has three selectable settings of 700 LM, 900LM and 1500 LM.
 13. The lamp as recited in claim 8, wherein the switchpositioned on the housing has three selectable settings of 2700K, 3500Kand 4000K.
 14. The lamp as recited in claim 8, wherein receiver forreceiving signal from the remote ON/OFF switch receives said signal forone of three selectable settings of 700 LM, 900 LM and 1500 LM.
 15. Thelamp as recited in claim 8, wherein receiver for receiving signal fromthe remote ON/OFF switch receives said signal for one of threeselectable settings of 2700K, 3500K and 4000K.
 16. (canceled)
 17. Alighting method comprising: housing a light source including at leastone string of light emitting diodes in a body of a lamp having adownlight geometry; and providing device circuitry that allows foradjustments to lumen settings and correlated color temperature settingsthrough an interface of setting switches fixed to the body of the lamp,wherein the setting switches are mounted on a back surface of the bodyof the lamp.
 18. The method recited in claim 17, wherein the methodfurther comprises providing a receiver for receiving from a remoteswitch adjustments to dimming and intensity settings for light emittedby the lamp.
 19. The method recited in claim 17, wherein the lightemitting diodes are surface mount device (SMD) light emitting diodes(LED).
 20. The method recited in claim 17, wherein the light emittingdiodes are chip on board (COB) light emitting diodes.